Programmable apparatus and method for delivering microingredient feed additives to animals by weight

ABSTRACT

A method and apparatus whereby livestock and poultry are administered feed additives in their feed ration. The apparatus stores additive concentrates separately until just prior to use, then on demand dispenses the additive concentrates into one or more weigh hoppers for weighing therein. The weighed contents of the weigh hoppers are discharged into a liquid carrier within a mixing vessel where the dispensed additives are diluted, suspended, and dispersed by mixing. The resulting carrier-and-additive slurry is pumped to a receiving station for mixing with a feed ration. The weighing components are isolated from movements that would affect additive weight determinations during the weighing process so that accurate measurements of additive weights are obtained. Dispensing and weighing of multiple additives within a single weigh hopper are sequential. Each additive may be weighed and discharged from the hopper individually or cumulatively with other additives. With multiple weigh hoppers, dispensing, weighing and discharge of additives from the different hoppers can occur simultaneously or independently. A programmable control can program the apparatuses for dispensing either entirely on a weight basis, partly on a weight basis and partly on a metering basis, on a weight-compensated metering basis, or entirely on a metering basis if the weighing means malfunctions.

This is a division of application Ser. No. 137,501, filed Dec. 22, 1987,now U.S. Pat. No. 4,815,042, which is in turn a continuation-in-part ofapplication Ser. No. 833,904, filed Feb. 26, 1986, now U.S. Pat. No.4,733,971 issued Mar. 29, 1988.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the administering of feed additives tolivestock, and more particularly to a method and apparatus forsupplementing the diets of livestock and poultry with feed additivessuch as nutrients and medicines supplied in a consumptive fluent carriersuch as water.

2. General Discussion of the Background

It has long been a common practice to feed additive supplements tocattle and other livestock, including poultry. Such supplements includevitamins, minerals, proteins, enzymes, hormones, antibiotics, wormmedicines, and other nutritional supplements and medications, whichprovide a balanced diet, protect the livestock from disease, andstimulate growth.

An early method of feeding additives to livestock involved the use ofcommercially prepared additive premixes. The additives were premixedtogether in dry form, with some dry diluting filler material, and thenstored at the feedlot for a period of time until ready for use. Thepremix was either mixed with the feed ration before delivery to theanimals or spread on the feed at the feed trough. Premixes suffer thedrawbacks of being costly to buy, store and administer. They aredifficult to mix evenly with the feed, and additives of differentdensities tend to segregate in premixes, increasing the chances thatspecific animals will receive too much or too little of a givenadditive. Too much of especially toxic additives can have dangerous oreven lethal consequences.

Additives also tend to lose their potency in premixes through physicalor chemical breakdown, especially if stored for a long period of timeunder changing environmental conditions in combination with otheradditives. Therefore, there is no assurance that livestock receive theirintended dosages of specific additives when the additives areadministered in premixes.

Premixes also limit the choices of additive combinations that livestockfeeders can feed their animals to those combinations availablecommercially. They also limit a feedlot's flexibility to feed differentgroups of animals different combinations and dosages of additives tomeet their differing needs.

Many of the foregoing problems were solved by the methods and apparatusof U.S. Pats. Nos. 3,437,075; 3,498,311; 3,822,056; 3,670,923; and3,806,001, which are commonly assigned to the owner of the presentapplication. These patents disclose various methods and apparatus forseparately dispensing at the feedlot, separately stored livestock feedadditive concentrates into a flow of fluent carrier material fordilution, dispersion and suspension, and for transporting the resultingslurry into livestock drinking water or feed rations shortly before thetime of intended consumption. Each of these methods and apparatus,however, meter the desired amount of each feed additive on a volumetricbasis. Volumetric metering can be inaccurate because of changes in thedensities of additive concentrates caused by variations in humidity,particle size, moisture content, flow characteristics, temperature, oilcontent and other factors. Even minor inaccuracies in the amount ofadditive concentrates dispensed can cause serious problems, since someof the additives are very potent, toxic drugs. Typically, only 10 to 100grams of a given additive concentrate are dispersed in a ton of feed.Volumetric metering is only accurate to within 1-2% even under the bestof conditions.

Therefore, there is a need for a more accurate method and means fordispensing additive concentrates in systems for delivering additivesinto feed rations at the feedlot, just before the time of intendedconsumption of the ration. One potentially more accurate approach is todispense additive concentrates by weight rather than volume. It isbelieved that at least one weigh-type additive concentrate deliverysystem has been tried, but unsuccessfully. It is believed that suchsystem weighed and then dispensed each additive separately andsequentially. It is believed that such system was unsuccessful becauseit was too slow and too inaccurate for handling additive concentrates ina feedlot environment.

U.S. Pat. No. 2,893,602 and U.S. Pat No. 3,595,328 disclose machines forweighing batch amounts of aggregate mixtures such as asphalt. Each ofthese machines uses a scale or strain gauge to measure the amount ofbulk material dispensed from a storage container. These systems are onlysuitable, however, for making the gross kinds of measurements needed indispensing and mixing bulk materials such as aggregates for makingasphalt or concrete, and feed grains for making feeds in commercial feedmills. The weighing components of these machines, for example, are notable to weigh gram amounts of materials as would be required foradditive concentrate dispensing in feedlots. Even if they were able tomake such fine measurements, their scales would be affected byenvironmental conditions commonly found at feedlots such as wind andmovement of machine components that would adversely affect theiraccuracy to an unacceptable extent. Finally, these devices would loseaccuracy progressively because of a buildup of residue of aggregateparticles in their weighing containers during use. They would thereforebe unsuitable for dispensing additive concentrates in a feedlotenvironment.

Accordingly, a primary object of the present invention is to provide anew and improved method and means for dispensing and delivering feedadditive concentrates in various combinations and dosages to livestockusing primarily weight-controlled rather than volumetric dispensing ofadditive concentrates.

Another primary object is to provide a new and improved method andapparatus for dispensing and delivering combinations of feed additiveconcentrates in a liquid slurry to a livestock feed ration at feedlotswhich is more accurate than prior such methods and apparatus.

Another object is to provide a method and apparatus as aforesaid whichcan be operated selectively either on a weight or volumetric basis.

Another object is to provide a method and apparatus as aforesaid thatcan be used effectively in a feedlot environment.

Still another object is to provide such an apparatus and method with animproved control system that can be controlled by a central processingunit that can be quickly and conveniently programmed to meet the varyingneeds of a given feedlot and different feedlots.

Another object is to provide a method and apparatus that are flexible inenabling the dispensing and weighing of two or more additives eithersimultaneously or cumulatively, or both, and in enabling the dischargeof each weighed additive into a diluting liquid carrier eitherindividually before other additives are weighed or together with otherweighed additives.

Finally, it is a specific object of the invention to provide a methodand apparatus as aforesaid which can accurately dispense gram amounts ofpotent microingredient additive concentrates to accuracies within 0.5grams.

SUMMARY OF THE INVENTION

The aforementioned objects are achieved by providing a method andapparatus for measuring, dispensing, and delivering differentcombinations and proportions of microingredient feed additiveconcentrates on primarily a weight basis in small but accurate amounts,into a liquid carrier. The carrier and concentrates form a slurry whichis delivered into a livestock or poultry feed ration shortly before thefeed ration is delivered to the animals for consumption. The apparatusincludes multiple dry and liquid additive concentrate storage means forstoring the various additive concentrates separately at the feedlot. Aplurality of separate dispensing means, such as conveyor screws for thedry additives and pumps for the liquid additives, dispense separatelyand without intermingling the additive concentrates from each of thestorage means into a receiving means such as separate compartments of ahopper or multiple weigh hoppers. Weighing means are provided fordetermining the weights of the different additives dispensed and forstopping the dispensing of each additive when a predetermined weight ofthat additive has been dispensed. The weigh means, for example, maycomprise a weigh scale means supporting each weigh hopper or supportingthe storage means.

In a preferred embodiment shown and described, the weigh hopper isscale-mounted, and the additives are dispensed and weighed sequentiallyand cumulatively as they are added to the weigh hopper. Isolating meansisolate the weighing means from movements affecting its weighingfunction so that accurate weight determinations are obtained. A controlmeans, such as a central processing unit, controls separately theoperation of each dispensing means to dispense a given microingredientadditive from a given storage means until a predetermined weight of thatmicroingredient has been dispensed and weighed. When all selectedadditive concentrates have been dispensed into the weigh hopper andweighed, the hopper deposits its contents into a liquid carrier withinanother portion of the receiving means comprising a mixing vessel. Theliquid carrier and additive concentrates are intermixed in the mixingvessel to dilute, dispense and suspend the additives in a liquid slurry.The slurry is then delivered to a receiving station where it is eithersprayed directly into and mixed with a feed ration or held forsubsequent addition to a feed ration.

The control means of the apparatus includes means for operating theapparatus either in a weigh mode, or, for example, if the weigh means isinoperative, in a volumetric dispensing mode.

The control means may include a programmable controller, programmable tocause the apparatus to dispense microingredients either entirely on aweight basis, partly on a weight basis and partly on a volumetric(metering) basis, on a weight-compensated metering basis, or entirely ona metering basis if, for example, the weighing means malfunctions.

The isolation means may include a separate, independently mounted andisolated weigh subframe assembly for the weighing components of theapparatus. Within the subframe assembly, scale components may be furtherisolated from other components. Further isolation may be provided by anindependent main frame surrounding the subframe and protecting it fromexternal forces by protective panels.

The weigh means may include multiple weigh hoppers, each for weighingone or more different additives. Different additives may be dispensedinto the multiple weigh hoppers and weighed simultaneously to speed upthe makeup of a batch formulation of additives. Where multiple additivesare dispensed into each weigh hopper, the hopper may be discharged aftereach additive is weighed or only after all additives are weighedcumulatively.

Where multiple weigh hoppers are used, each includes its own independentweighing means to enable weighing of multiple additives to occursimultaneously. Each weighing means includes a scale head that takes aweight reading many times per unit of time, averages such readings, andthen transmits the averaged reading to the central processing unit onlyonce during the same unit of time, thereby minimizing the effects of anyerroneous weight reading induced by extraneous or other transientfactors.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the present invention willbecome more apparent from the following detailed description whichproceeds with reference to the accompanying drawings wherein:

FIG. 1 is a perspective view showing the major components of anapparatus in accordance with the present invention.

FIG. 2 is a schematic perspective view illustrating the internalcomponents of the main cabinet shown in FIG. 1.

FIG. 3 is an enlarged, perspective view of a typical foot portion andisolation pad of a support leg of the apparatus of FIG. 1.

FIG. 4 is an enlarged, front elevational view of the main cabinet shownin FIG. 1, the cabinet panels having been removed to show the internalparts of the machine.

FIG. 5 is an enlarged, perspective view of the weigh frame subassemblyof the apparatus shown in FIG. 4.

FIG. 6 is an enlarged, fragmentary, perspective view of a load cell in aweigh tower of the weigh frame of FIG. 5, the remainder of the weighframe being broken away.

FIG. 7 is an enlarged, fragmentary perspective view of a portion of theweigh hopper subassembly of the weigh frame shown in FIG. 5.

FIG. 8 is a fragmentary top perspective view of a dry additivedispensing means portion of the apparatus of FIG. 4, shown mounted onthe main frame assembly of FIG. 4;

FIG. 9 is a fragmentary top perspective view of the mixing vessel andassociated components of the main frame assembly shown in FIG. 4;

FIG. 10 is a plumbing diagram for the fluid components of the apparatusof the preceding figures;

FIG. 11 is a schematic view of the air flush system for the weigh hopperportion of the apparatus;

FIG. 12 is a flow diagram illustrating the logic of a computer programwhich controls the weigh means of the present apparatus.

FIG. 13 is a flow diagram illustrating the logic of a computer programwhich controls all machine operating sequences and functions other thanthe weigh functions illustrated in FIG. 12.

FIG. 14 is an electrical control schematic diagram for the illustratedapparatus.

FIG. 15 is a flow diagram illustrating the logic of a computer programwhich controls alternative volumetric metering and dispensing functionsof the illustrated apparatus;

FIG. 16 is a schematic view illustrating a first alternative embodimentof the invention in which microingredient additive concentrates aredispensed directly into a mixing vessel from individually weighedstorage containers.

FIG. 17 is a schematic view illustrating a second alternative embodimentof the invention in which dry additive concentrates are dispensed byweight into a weigh hopper while liquid additive concentrates aremetered by volume directly into the mixing vessel.

FIG. 18 is a schematic view showing a third alternative embodiment ofthe invention in which different additive concentrates can be dispensedinto different weigh hoppers simultaneously and the different weighhoppers discharged either independently or simultaneously and eitherafter the weighing of each additive or cumulatively after the cumulativeweighing of multiple additives in each hopper.

FIG. 19 is a flow diagram illustrating the logic of a modification ofthe computer program of FIG. 15 which controls a hybridvolumetric-weight system of measuring the amounts of microingredientsdispensed using apparatus of the general type shown in FIG. 16.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Introduction

The microingredient feed additive concentrates of the present inventioninclude such potent substances as hormones, antibiotics, and vitaminsthat are typically administered to cattle and poultry at feedingoperations, such as cattle feedlots, in gram amounts or less. It isoften essential that a prescribed amount of a microingredient bedelivered to an animal, and no more. Too little of a microingredient hasno effect, while too much of it may be toxic or fatal. The range betweentoo much or too little of some additives is often no more than 0.5 gram.The apparatus and method disclosed in this detailed description isintended to accurately dispense dry and liquid additive concentrateswithin this range of accuracy.

General Assembly

With reference to the drawings, FIG. 1 illustrates an apparatus showngenerally at 10 for measuring, dispensing, and deliveringmicroingredient feed additive concentrates in small but accurateproportions in a liquid carrier slurry to livestock shortly beforedelivery of the feed ration to the animals for consumption. Theapparatus 10 includes several separate components including a maincabinet 11, and a remote control unit 20, shown for convenience nearcabinet 11 but normally located at a remote control station such as at afeed truck filling station in a feedlot. Additional separate componentsinclude multiple liquid additive concentrate storage containers 76, 78(only one being shown in FIG. 1) supported on a stand 79, and theirdispensing pumps 79 (see FIG. 2). Typically, a separate water supplytank 195 (FIG. 14) supplies the necessary carrier and flush water to thecabinet through fill and flush conduits (FIG. 10), via a booster pump193 (FIG. 14).

Another separate cabinet (not shown) houses a weigh micro computer, orcentral processing unit, shown schematically at 424 in FIG. 14. A secondmicrocomputer, or central processing unit, shown schematically at 430 inFIG. 14, for controlling the machine sequencing and volumetric meteringfunctions, is housed within one end portion 13 of cabinet 11. Variousspeed controls and electrical relay interfaces and circuitry of thecontrol system shown in FIG. 14 are also housed within cabinet endportion 13. Such end portion is a separate compartment of cabinet 11that can be swung open about a hinged vertical axis for access.

Cabinet 11 houses the major mechanical components of the apparatus. Theexterior of the cabinet, with its protective panels 12, completelyencloses and shields such components from external dust, dirt and othercontaminants common in a feedlot environment. The panels also protectthe internal components, especially the weight-sensitive ones, fromexternal forces such as wind, jarring contact, and the like, that wouldotherwise affect the accuracy of weight measurements.

Referring to FIG. 4 showing the major components inside the cabinet 11,such components include a main frame 46 and an entirely separate andindependently mounted subframe 34, each mounting certain components.Access to the components mounted on these frames is gained throughaccess doors 15, 17, 19 in a front wall of the cabinet 11, and throughhinged lids 16, 18 on a top wall of the cabinet.

In general, weigh subframe 34 mounts those components which arenecessary to the weighing function of the apparatus, and main frame 46mounts the remaining components that could, during their operation,induce undesirable movements in the weigh components to adversely affectthe weighing function. Accordingly, the weigh subframe serves as a meansfor isolating the weigh components from internal machine movementsinduced through operation of components on the main frame.

The main frame components include storage bins 68, 70, 72, 74 forstoring different dry additive concentrates, dry additive dispensingmeans 80 for dispensing additives from the storage bins, and anadditive-receiving means comprising a mixing vessel or tank 170. Othermain frame-mounted components include a discharge pump 244 for pumpingslurry from mixing vessel 170, slurry mixers 180, and various plumbingcomponents for supplying carrier and flush water to the mixing vesseland discharging slurry liquid from the vessel. Cabinet lids 16, 18provide access to the storage bins for refilling them.

The subframe 34 includes an entire subassembly of weigh components,including a weigh hopper means comprising the compartmented weigh hopper122, and a suspension means for suspending the weigh hopper from aweighing means 250. The suspension means includes a pair of suspensionframes 123, one at either end of the weigh hopper. Each such framerotatably supports weigh hopper 122. Each suspension frame 123 includesa suspension arm 270 suspending the suspension frame from the weighmeans 250. The weigh means includes, at each end of the subframe 34, aweigh tower 252 projecting upwardly from the subframe and suspendingtherein a load cell 264. The load cell in turn suspends the weigh hopperthrough an appropriate connection to suspension arm 270 of suspensionframe 123.

Remote control unit 20 includes a computer terminal 22 supported on astand 30 having a base plate 32. Terminal 22 includes a primary keyboard24, a primary display screen 26, a small, secondary keyboard 27 and asmall, secondary display screen 29. Various control switches andindicators are provided on a control switch box 28 mounted on a shelf 31of the stand below the terminal 22.

Weigh Frame Subassembly

Apparatus 10 is seen therein and in FIG. 5 to comprise a weigh frame 34having four uprights 36 and two each of parallel crossbeams 38, 40 andlongitudinal beams 37, 39 rigidly interconnecting the four uprights 36.A vertical slat 41, 43 is carried between each pair of beams 37, 39.Each of uprights 36 has an enlarged foot 42 to enhance the stability ofweigh frame 34. Each foot 42 is mounted on an elastomeric isolation pad44 (FIG. 3) which absorbs vibrations or other environmental influencesthat may affect the accuracy of the functions performed by weigh frame34. Each pad 44 includes a square upper plate 45 to which foot 42 issecured, the upper plate having a peripheral, downwardly dependingflange which forms an enclosure. A square lower plate 47 is attached toa floor with bolts below plate 45 and has a peripheral, upwardlyextending flange that forms an enclosure. A rubber cushion 48 is placedbetween plates 45, 47 within the enclosures formed by the flanges on theplates. Cushion 48 is thick enough to maintain the upwardly anddownwardly extending flanges in spaced relationship so that vibrationsare not communicated between plates 45, 57.

Main Frame Subassembly

Separate mounting or main frame 46 substantially surrounds weigh frame34, the mounting frame 46 comprising four uprights 49 interconnected byfour top support beams 50 and four bottom support beams 52. Twointermediate parallel support beams 51, 53 extend across opposingparallel faces of frame 46, and two parallel support beams 54, 55 extendacross the middle of frame 46 parallel to beams 51, 53. A pair ofparallel, U-shaped brackets 56, 57 are fixed to and suspend from beams51, 54 (FIG. 8), and a pair of similar U-shaped brackets are fixed toand suspend from beams 53, 55. Only one U-shaped bracket 59 is shown inFIG. 4, although it will be understood that a second, parallel U-shapedbracket extends between beams 53, 55 in an arrangement similar to thatshown in FIG. 8 for U-shaped brackets 56, 57.

Mounting frame 46 is supported by casters 58 each having a roller 60that is received within a cup 62 that is attached to an isolation pad 64which is similar in structure to pad 44 shown in FIG. 3. Pad 64comprises a top plate 65 having a peripheral, downwardly dependingflange and a bottom plate 66 bolted to the floor and having aperipheral, upwardly extending flange. A rubber cushion 67 is positionedbetween plates 65, 66 within the enclosures formed by their peripheralflanges, the width of cushion 67 being great enough to keep theperipheral flanges in spaced relationship to one another and avoid metalto metal contact which might transfer vibrations.

FIGS. 2 and 4 show multiple storage means such as dry additiveconcentrate storage bins 68, 70, 72, and 74 for storing separately aplurality of different dry microingredient feed additive concentrates.Each of the bins has a square top opening and square bottom opening, thebottom opening having a smaller area than the top opening such that thecross-sectional area of each bin diminishes in the direction of thebottom opening. A pair of vibrator motors 75, 77 (FIG. 4) are placed oneach bin 68-72 to assist in moving dry microingredient concentrates outof the bins during dispensing.

A plurality of liquid containers 76, 78 are also shown in FIG. 2 forstoring separately different liquid microingredient feed additiveconcentrates. The liquid containers are supported on a table 79 (FIG. 1)adjacent cabinet 11 and connected to the apparatus through flexibletubes described later.

A separate dry dispensing means 80 is provided for each dry bin 68-74. Aseparate liquid dispensing means 120 is provided for each liquidcontainer 76-78. Each liquid and dry dispensing means is independentlyoperated and controlled for dispensing separately several selectedadditive concentrates from their respective bins and liquid containersin predetermined weights during a machine operating cycle.

One of the dry dispensing means 80 for a dry microingredient is shownbest in FIGS. 4 and 8. It includes an annular collar 82 having a squarecross section. The collar fits closely about the open bottom of a bin68-74 and extends partially up its sidewalls. Collar 82 has a squarefrusto-pyramidal configuration which defines a flow passageway ofprogressively decreasing cross section from the bottom bin opening to atop opening into a coreless metering screw assembly 84 within arectangular lower extension section 86 of collar 82 having a curvedbottom. Screw assembly 84 includes a rotatable core 88 which carries ahelical metal screw 90 and rectangular screw agitator 92 with a circularband 94 around one end thereof. A stationary rear one-half tubeextension 96 of a conveyor tube 108 projects into the interior ofagitator 92 to start the conveyance of material that is moved by thescrew 90 into conveyor tube 108. Agitator 92 helps maintain a uniformmicroingredient density around rotating screw 90.

Agitator 92 is rotated by a shaft 100 which is driven through aright-angle gear box 104 by a variable-speed motor 102, with threepre-set speeds. Core 88 and screw 90 project through opening 106 andinto conveyor tube 108 having an open end that terminates adjacent adeflection plate 110 above the top opening of weigh hopper 122. Thus themetering screw assembly conveys additive from the supply bin into acompartment of the weigh hopper.

Each of liquid containers 76, 78 is provided with a separate dispensingmeans 120. Each liquid dispensing means is, for example, avariable-speed or displacement rotary or piston pump 79 (FIG. 2). Theliquid dispensing means pumps liquid additive from a container 76,78through a flexible feed conduit which connects to a rigid dispensingtube end 120 (FIG. 5) on the weigh subframe to deliver the additive intoa liquid compartment 117-118 of weigh hopper 122.

The hopper 122 (FIGS. 2, 4, 5, and 7) is carried by weigh subframe 34between frame slats 41, 43 below the open end of extension tube 108 ofscrew conveyor 80. Hopper 122 is an elongated trough having asubstantially semicylindrical cross section and a plurality ofpartitions 112 which divide the hopper transversely into several drymicroingredient receiving compartments 113, 114, 115, 116. Each of thedry compartments 113-116 is provided with a deflector 132 on itspartition wall having a triangular cross section that directs additiveconcentrates to the interior of the compartments during both filling andemptying of the hopper.

Additional partitions 111 of hopper 122 cooperate with some partitions112 and upper walls 128 to define liquid additive-receiving compartments117, 118 having narrow openings 130 into which liquid dispensing tubes120 direct liquid additives from containers 76, 78.

The liquid and dry additive compartments of hopper 122 maintaindispensed additives separated until the hopper discharges its contents,after weighing, into the diluting liquid carrier within the mixingvessel 170 positioned vertically below the hopper.

Hopper 122 is supported by weigh frame 34 such that it is free to rotateabout its longitudinal axis. Each semicircular end plate 134 (one beingshown in FIG. 7) of hopper 122 is secured to a shaft 136. The shaft 136at the hopper end shown in FIG. 7 is drivingly connected to a motor 138that is fixed to hopper suspension frame 123 by a mounting bracket 273.The shaft at the opposite end of the hopper is mounted in a bearing 140(FIG. 4). Motor 138 operates first to rotate hopper 122 to an invertedposition for emptying (FIG. 11); then to an upright position (in thesame direction) for the next dispensing and weighing cycle.

An air flush means for compartments 113-116 of hopper 122 is shown inFIG. 11. The air flush means is carried by the main frame and comprisesa compressor 142 in fluid communication through passageway 144 with airpressure accumulator tank 146. A solenoid valve 149 regulates the flowof air through passageway 148 to header 150. The header in turn fluidlycommunicates with a plurality of hoses 152 that project into eachcompartment 113-116 of hopper 122 when the hopper is inverted Each ofhoses 152 is positioned to direct a stream of air against far wall 154of the hopper. It is not necessary to direct the air stream against nearwall 156 because that wall will have already been scraped relativelyclean by the movement of dry additives against the wall and out of thehopper as hopper 122 rotates to an inverted position.

A vibrator motor 141 is carried by suspension frame 123 at the end ofhopper 122 opposite hopper rotating motor 138. Vibrator motor 141operates during inversion of the hopper to promote emptying of thehopper compartments by vibrating the hopper.

An elongated mixing vessel 170 which serves as a receiving means forreceiving additives from the hopper 122 and also as a mixing means formixing such additives with water, is placed below hopper 122. Vessel 170is an elongated tub that is longer and wider than hopper 122. Vessel 170comprises a continuous, annular upright wall 172 around a sloping bottomformed from a plurality of triangular sections 176 that slope towards apair of central bottom openings including an inlet port 177 anddischarge port 178.

Variable speed flow inducing means, such as variable two-speed mixers180, serve as part of the mixing means and are provided in mixing vessel170 for inducing a turbulent flow of liquid within the mixing vessel.Each mixer 180 is comprised of four angled mixing blades 182 connectedto the end of a rotary mixing shaft 184 that is connected to a gearbox186 and motor 188 for rotating shaft 184. Each of motors 188 is mountedon a motor mounting frame 190 along an outside face of vessel wall 172.Level sensors 192, 194 are also mounted over the edges of wall 172 andproject downwardly into the tub for determining the level of watercontained therein and shutting off a supply of water to the tub when apredetermined level is reached. Sensors 192, 194 are, for example,electrodes through which an electrical circuit is completed or a timingcircuit energized when the water surface in the tub reaches thepredetermined level. Sensor 192 is the primary sensor, while sensor 194is a backup sensor which detects a near overflow condition, closes fillsolenoid 206, and interrupts the fill cycle.

FIG. 10 shows a plumbing system for apparatus 10 which delivers andremoves carrier and flush water from vessel 170. Water is introducedfrom a source 195 by pump 193 through line 194 where its pressure isdetected by pressure gauge 196. Water then continues to flow throughline 198 where it is divided by tee 200 into water lines 202, 204. Theflow of water through fill line 204 is controlled by solenoid valve 206which, when open, allows water to flow through line 208, thence toconduit 210 and into vessel 170 through port 177. When solenoid valve206 is open, a second solenoid valve 212 in line 202 remains closed suchthat all of the supply of water moves through line 204 to fill vessel170.

Solenoid valve 212 is interposed between line 202 and flush line 214that in turn communicates with line 216 to establish fluid communicationwith conduit 210. Line 214 also fluidly communicates with line 218having branches 220, 222. Branch 220 fluidly communicates with a pair ofnozzles 224, one positioned above blades 182 of each mixer 180, nozzle224 directing a flow of water onto the blades to clean them. Line 222provides a passageway through which the water moves to flush ring 226(FIGS. 9 and 10) which is positioned around the upper inner periphery ofvessel 170 adjacent its top edge. Ring 226 has a number of flush nozzles228 which direct a flow of water downwardly against wall 172 of vessel170 to flush it.

Apparatus 10 also has a delivery means for delivering slurry from vessel170 to a receiving station for mixing with an animal feed ration at alocation remote from the mixing vessel. This delivery means includesdischarge opening 178 in fluid communication with conduit 240 thatempties into discharge line 242. Discharge pump 244 withdraws slurrythrough line 242 and sends it through line 246 to receiving station 248where, typically, it is sprayed into a livestock feed ration and mixedtherewith.

Weigh Means

A weighing means 250 (FIG. 6) is provided on weigh frame 34 for weighingpredetermined weights of the different additive concentrates dispensedfrom bins 68-74 and containers 76, 78. Weighing means 250 includes aweigh tower 252 extending vertically upward from a crossbeam 40 of weighframe 34 midway between uprights 36 at each end of frame 34. Each tower252 has a flat top plate 254 with a central opening through which thethreaded shank of an eye member 256 is placed and secured with a nut. Arubber pad 258 is placed against the interior face of plate 254 beforemember 256 is secured to top plate 254 with the nut. A pair ofsuspension members 260 pivotally interconnect eye member 256 and asecond eye member 262 from which a load cell 264 is suspended. Theamount of strain on load cell 264 is communicated to a control unitthrough line 265. The load cell 264 in the preferred embodiment iscapable of weighing to an accuracy of 0.5 grams.

A rubber isolator pad 266 is pivotally suspended beneath load cell 264by suspension members 268. A suspension arm 270 of the hopper suspensionframe 123 is in turn suspended from isolation pad 266 by hook 272 andeye 274 secured to arm 270. Arms 270 of suspension frames 123 thussuspend hopper 122 such that the entire weight of the hopper is freelysuspended from load cells 264. Arms 270 are braced by gussets 271 totheir rectangular weigh frames 123. Hopper 122 is suspended interior toframes 123 between slats 41, 43 of frame 34 by suspending shafts 136,one of which is driven (FIG. 7) and the other of which is mounted in abearing 140 (FIG. 4). The hopper is therefore free to rotate betweenframes 123 to an inverted position. This arrangement allows the weightof the hopper to be transferred through frames 123 to arms 270 foracting on load cells 264. The weight of additive concentrates in hoppermeans 122 can therefore be accurately determined.

As best shown in FIG. 7, a transverse vibration and sway dampening rod276 extends between a bracket 278 carried by an upright of hoppersuspension frame 123 and a bracket 279 carried by two longitudinal beams37, 39 of weigh frame 34. Such a rod 276 is provided at each end ofweigh frame 34 adjacent face 134 of hopper 122 for preventing or dampingtransverse movements of the hopper. A similar longitudinal rod (notshown) extends along one longitudinal side of hopper 122 to prevent ordampen longitudinal vibratory or swaying movements of hopper 122, oneend of the longitudinal rod being fixed to longitudinal beam 39 and theother end being fixed to weigh frame 34. Such sway dampening rodsprovide part of the means isolating the weight-sensitive components ofthe apparatus from movements that could affect accurate weightmeasurements.

Control Means

Apparatus 10 is provided with a control means, such as a centralprocessing unit, for controlling the operation of apparatus 10. In thepreferred embodiment, two-programmed central processing units are used,one for operating the weighing functions of apparatus 10 and the otherfor operating all other machine functions.

Weighing Program

The logic of the program for operating the weighing functions of themachine is shown in FIG. 12. The weighing CPU is activated by startingthe menu at 280 and then entering ration data with keyboard 24 for aparticular feedlot or data for one of a series of desired batches at afeedlot. The formulation of each desired batch has been preprogrammedinto the computer such that a batch formulation can be chosen byentering a code number at 282. The computer then searches at 284 for amatch to this encoded formulation until the match is found and themachine is ready to batch. If a match is not found, the program at 285returns to step 280 and a prompt is sent to screen 26 to enter rationdata.

Once a match is found at 284, a program prompt at 286 appears on screen26 requesting the size of the batch to be prepared. After thisinformation is entered, the program prompt at 287 requests the number ofbatches to be prepared, and if the batch size exceeds the capacity ofthe preprogrammed limit for the feed lot ration mixer or thecompartments 113-118 of hopper 122, this is computed at 288. If capacityhas been exceeded, a prompt is sent to screen 26 at box 289, and theprogram will request that new data concerning batch size and number beentered by returning to step 286. If capacity has not been exceeded, themachine is ready to batch at 290.

The weighing computer first checks to determine if a weigh switch is onat 292, and if the weigh switch is off, an alarm is sounded at step 293and the program returns to ready at 290. The alarm will alert anoperator that the weighing switch must be turned on in order forbatching to continue.

The program next calculates metering ration data at 294 and sends it tothe machine operating program at 295 as indicated by A in FIGS. 12 and13. The metering data is calculated for any additives that have beenselected for dispensing in the metering mode during the weigh cycle.Dispensing a portion of the additives by volume is more fully set forthin connection with steps 361-363 of FIG. 13 below.

The program then sets an output for the water level at 296, the level ofthe water determining how much fluid carrier will be present in theslurry which is ultimately delivered to receiving station 248. Waterlevel information is sent to the machine operating program at 297, asindicated by B in FIGS. 12 and 13. The program next waits at 298 for astart signal which the operator gives by activating start switch 299 onswitch panel 28. The weighing cycle is then started at 300 by sending astart signal at 301 to the machine operating program as indicated by Cin FIGS. 12 and 13. Even though the weighing cycle has started, noweighing of microingredients actually commences until a signal isreceived back from the machine operating program at 302 as indicated byD in FIGS. 12 and 13 that indicates weighing should begin at 304. Thiscommunication between the programs at D enables the machine operatingprogram to begin its initial checks while microingredients are beingdispensed and weighed.

Once the signal to begin weighing is received at 304, the weighingsequence begins at 306. It is first determined at 308 whether a motionsensor is detecting movement of hopper means 122. Information isreceived from the motion sensor on the hopper at 309, as indicated by Ein FIGS. 12 and 13. The program will not progress beyond 308 until themotion sensor indicates that hopper means 122 is not moving, sincemovement of the hopper means will adversely affect weight determinationsof load cell 264. Hopper means 122 can be put in motion by a variety ofinfluences, such as wind gusts, floor vibration, personnel contact, ormovement of machine parts. Although the effect of these movements onload cell 264 may not be great, the extreme accuracy required indispensing microingredient feed additive concentrates makes absence ofmovement desirable.

It is next determined at 310 whether the scale reading is less than 1000grams. If the reading is greater than 1000 grams, it is probably becausethe hopper means is not empty, as indicated at 311, and a signal is sentat 312, 313 to dump hopper means 122 so that weighing of a new lot ofmicroingredients can begin. The signal to dump is sent to the machineoperating program as indicated at step 314 and F in FIGS. 12 and 13. Themixers 182 are also started at 315 as indicated by G in FIGS. 12 and 13so that the microingredients dumped from hopper means 122 will be mixedinto a slurry and discharged to receiving station 248 in accordance withnormal operation of the machine operating program described inconnection with FIG. 13 below.

If the scale reading is less than 1000 grams, it is determined at 316 ifthe scale reads below zero. If that is the case, a message is given tothe operator by 317 on screen 26 that the scale has failed and thesupervisor should be called. Then at 318 the program prompts theoperator to switch to a backup metering mode system which dispensesadditive concentrates by volume instead of by weight, and a prompt issent at 319 to screen 26 directing that the weigh switch 321 at panel 28be turned off. The operator then performs as outlined in FIG. 15 byturning the meter switch on at step 500 and entering ration data at 502.Volumetric metering of additive concentrates is performed by activatingmotor 102 of each bin 68-74 to rotate screw 90 for a predeterminedperiod of time. Since screw 90 will dispense an approximate known amountof concentrate per unit of time, a volumetric approximation of thedesired amount of concentrate can be dispensed without weighing.

If the scale reads above zero at 316, the weighing mode of the programis instead used. Ingredient flow is started at 320 by activating motor102 for screw 90 below bin 68. Motor 102 has at least two speeds so thatit initially operates at a higher speed during the initial phase ofdispensing additive concentrates from bin 68 into a first compartment113 of hopper means 122. The weight of concentrate introduced intocompartment 113 is sensed by load cell 264 and that information iscontinually fed back to the computer through line 265. As the weight ofconcentrate dispensed from bin 68 approaches the predetermined amount ofthat concentrate for the batch formulation chosen at 282, motor 122 isswitched to a lower speed at 322 and 324 that more slowly dispenses theconcentrate from bin 68 during a final phase of dispensing. In thismanner, a more accurate weight of microingredient can be dispensed frombin 68 into compartment 113 since the dispensing of additive will haveslowed before it is finally stopped when the correct weight of thisfirst concentrate is sensed at 326.

The program contains a weight compensation step at 328. It sometimeshappens that the actual weight of additive concentrate dispensed bydispensing means 80 into compartment 113 will be slightly greater orless than the desired weight set by the ration data at 282. The programcompensates for such inaccuracies by adding or subtracting a weightcompensation factor to the ration amount set for the additiveconcentrate at 282. In this manner, the weight inaccuracy will becorrected the next time a microingredient additive is dispensed from bin68 into compartment 113.

When the predetermined weight of microingredient additive concentrate issensed at 326 and the weighing of that component has been completed, thecomputer determines if the just dispensed concentrate was the lastmicroingredient dispensed at 330. Assuming the microingredientconcentrate in bin 68 was not the only concentrate to be dispensed inthis formulation, the program then returns to box 320, and the flow ofingredients from bin 70 is initiated by activating motor 102 beneath bin70 to turn screw 90 at a fast speed and begin moving microingredientadditive from bin 70 into compartment 114 of hopper means 122. Load cell264 continues to sense the weight of concentrate added to hopper means122 from bin 70 until that weight begins to approach the finalpredetermined weight desired of the second concentrate. Thispredetermined weight will be the total actual net weights of the firstadditive concentrate plus the predetermined weight of the secondadditive concentrate since hopper means 122 has not yet inverted and thefirst additive concentrate still remains in compartment 113. As thetotal combined actual weight of additive concentrate in compartments113, 114 approaches the predetermined amount, motor 102 is switched to aslower speed, and additive concentrate is continued to be slowlydispensed with screw 90 from bin 70 until the total combined weight ofadditive concentrate is reached, and motor 120 is shut off.

This same procedure is repeated until the predetermined weight ofadditive from each of bins 72, 74 is similarly dispensed intocompartments 115, 116. Liquid microingredient additive concentrates fromcontainers 76 and 78 are dispensed by activation of a liquid pump whichsequentially dispenses liquid additive from containers 76, 78 intoliquid receiving compartments 117, 118 of hopper means 122 until apredetermined amount of each liquid additive has been dispensed.

Once the last additive has been dispensed, as determined at 330, thecomputer determines that weighing has been completed at 332, which sendsat 334 a signal to the machine sequence program as indicated by H inFIGS. 12 and 13. The computer pauses at 336 to wait on discharge ofhopper means 122. Once dumping of hopper means 122 has been completed byinversion of the hopper and its return to an upright position, thisinformation is sent from the machine operating program of FIG. 13 to theweighing program of FIG. 12 as shown at I and 338. It is then determinedat 340 whether another batch of microingredient is required. If not, theprogram returns from 342 to its starting point at 280. If another batchis required, the program returns to box 292 and the sequence repeatsitself as described above.

Although not shown in FIG. 12, the weigh program can be modified to keepa running inventory of additive concentrates. This can be accomplishedby entering into the weigh computer the weight of additive concentrateplaced in each of bins 68-74 and containers 76, 78. The weight of eachconcentrate actually dispensed and sensed by load cells 264 is thensubtracted from the original weight of concentrate to determine theinventory of concentrate remaining.

The control means can also be programmed to perform other functions thatenhance the accuracy of weight determinations by the weighing means. Forexample, the isolating means can include programming the control meansto prevent acceptance of the measured weight by the control meansfollowing operation of dispensing means 80 until motion of hopper means122 sensed by motion sensors has subsided to a level that will notaffect load cells 264. The same result can be achieved by programmingthe control means to delay operation of all other movable machinecomponents (such as dispensing means 80, 120 or mixers 182) for apredetermined period of time sufficient for hopper 122 to settle oruntil any oscillatory movements subside. Alternatively, the isolatingmeans can include programming the control means to prevent operation ofmoving components (such as dispensing means 80, 120 or mixers 182) whileweight determinations are being made by the load cells 264.

Machine Sequence Proqram

FIG. 13 schematically illustrates the logic of a program for actuatingthe sequence of operations of apparatus 10. The program begins bydetermining at 344 if the weigh switch on switch panel 28 has beenturned on. Once the weigh switch is on, the program is ready for ametering data signal at 345. It waits at 346 until the metering rationdata is received at 346 from steps 347 and 295 as indicated by A.

Once the metering data is received, the program is ready to batch at348. It receives water level data at 349 from 350 and 297 as indicatedby B. The start signal from 301 is then relayed via C to 351 and 352.The machine cycle is then started at 353, and initiation of the cycle issignaled to the weighing program from 354 through D to 302.

Boost pump 193 is then turned on at 355 for introducing water throughline 194 in FIG. 10 with solenoid 206 open and solenoid 212 closed. Itis determined at step 355 if the boost pump is on, and if it is not, analarm is sounded at 356 that the pump is switched off. Boost pump 193introduces water through line 208, conduit 210, and port 177 until apredetermined water level set at 294 is sensed by level probe 192. Ifthe predetermined water level is not reached within a set period of timeas indicated by 357, an alarm sounds at 358 to indicate that an errorhas occurred. Otherwise, if mixing vessel 170 fills within the set time,this condition is detected by level probe 192 and mixing blade motors188 are activated at 359 on a slow speed to cause the water in mixingvessel 170 to flow. If the motors 188 do not turn on, an alarm is givenat 360 to alert the operator of this malfunction.

It is possible to accurately dispense some liquid microingredientadditives such as those in containers 74, 76 by volumetric meteringinstead of weighing. Such accurate volumetric metering is possible sincethe density of most liquids is quite constant over the range ofenvironmental conditions in which apparatus 10 is used. Volumetricmetering of liquid additives selected by the metering ration data isachieved at 361 by activating the piston pump in dispensing means 120for a period of time determined by 362, 363. Once the metering step iscompleted, the dumping mechanism is enabled at 364 for proceeding toweigh complete step 365 before inverting hopper 122.

The program waits at step 365 for the weighing sequence shown in FIG. 12step 320 through step 334 to be complete. Once the weighing sequence iscompleted at step 334, a signal is sent to 365 through 366 at H from theweigh program, and the sequence program progresses to 367 where a signalis given at 368 from 314 via F to actuate motor 138 and invert hoppermeans 122 to dispense the additive concentrates contained incompartments 113-118 separately but simultaneously into the flowingwater of vessel 170. The dumping mechanism is disabled at 369 once thehopper leaves its upright position. Once hopper means 122 is inverted at370, vibrators on the hopper are activated at step 372 to promotecomplete removal of all microingredient particles from bins 113-118.Compressor 142 is next actuated at 373 to compress air in air tank 146,and a solenoid to header 150 is opened which moves a flow of air throughhoses 152 and toward wall 154 of each of compartments 113-116 to removeany traces of solid additive concentrates from the compartments. Airflushing continues for a predetermined period of time at step 373.

Hopper means 122 is then sent to its home position at step 374 byactivating hopper motor 138 to continue to turn shaft 136 in the samedirection it turned to invert the hopper. When the hopper returns to itsupright position, this is sensed by a switch as indicated by step 375,and a signal is sent at 376, 377 to 338 through I that the contents ofhopper means 122 have been dumped, and another weigh cycle (FIG. 12) canbegin. Meanwhile the machine operating program of FIG. 13 progresses tostep 378 which switches motors 188 of mixers 180 to a higher speed. Thelower motor speed is used until hopper means 122 leaves its invertedposition since high speed mixing while the hopper is inverted couldcause water drops to be splashed into containers 113-116. Step 378 alsobegins to measure a predetermined mixing time. When the period for thepreselected mixing time expires, as determined at 380, the mixing motors188 are switched back to their lower speed. Once the weighing programreceives a discharge signal at 381 from step 315 through G and 382, oralternatively from actuation of a discharge switch 383 on switch panel28, a discharge signal is sent by the program at 384 to discharge theslurry in vessel 170. A solenoid valve in line 240 then opens, and pump244 (FIG. 10) is activated to remove the slurry through outlet 178 invessel 170. Mixer blades 182 continue turning at a slow speed until apredetermined period of time expires, as set by step 385. Pump 244continues operating as the water level lowers and finally clears thebottom of probe 192, as illustrated by step 386. If the level probe isnot cleared within a predetermined period of time, an alarm is given at387 to indicate a pumping malfunction.

After the water level clears the bottom of probe 192, pump 444 continuesoperating and a timed flush cycle begins at 388. Boost pump 193 isactivated at 389 for introducing water through line 194 as solenoid 206is closed and solenoid 212 is opened. In this manner, flush water isintroduced through line 214 so that it enters vessel 170 through nozzles228 of flush ring 226, blade flush nozzles 224, and port 177. Theinterior of vessel 170 and the surfaces of blades 182 are therebyflushed, completely removing any residue of microingredient additivesfrom the vessel through inlet 179. The boost pump continues introducinga water flush into vessel 170 until the flush time period expires at390, and the flush is terminated at 391. Discharge pump 244 continuespumping for a delay period following the end of the flush cycle, asshown at 392; then discharge pump 244 is turned off at 393.

The program then determines if the weigh switch is still on at 394 andif it is, the program returns to step 344 to repeat the sequencedescribed in steps 344-393. If the weigh switch has been turned off, theapparatus 10 is turned off at 395 and an alarm is given at 396 toindicate that a mode change has been made.

The control means includes means for operating mixers 180 and dischargepump 244 at the same time as dispensing means 80 such that a first batchof additive concentrate slurry can be mixed and delivered to a receivingstation while a second batch of additive concentrates are dispensed andweighed prior to their deposit into the mixing vessel.

Electrical Schematic

A schematic diagram of the electrical connections for apparatus 10 isshown in FIG. 14.

It is important to the proper operation of a computer that it besupplied with electrical power of a constant and consistent quality.This is a serious drawback in rural areas where the electrical powerbeing supplied is often at the end of a long supply line into whichfluctuations are introduced by intervening power users. Most cattleyards and other users of apparatus 10 are located in rural areas wherevariations in power would adversely affect operation of the computerswhich control weighing and sequencing of machine function. For thatreason, the present invention employs a series of transformers toselectively filter the electrical energy, isolate the power source, anddamp variations in the power before it is supplied to the computers.

Four hundred eighty volts of power are supplied at 400 by a ruralelectrical utility, and that power first passes through 10 kw isolationtransformer 402 where it is transformed into 240 V power, illustrated by404 in FIG. 14. This initially filtered 240 V power is supplied toelectrical connection line 405 through relay 406 to booster pump 193that introduces water into mixing tank 170 during the filling andflushing cycles. The 240 V power is also supplied through relay 407 topump 244 that helps drain the mixing tank. This relatively unfilteredpower can be supplied to pumps 193, 244 since they are not as sensitiveto power variations as the computers.

The 240 V power is also sent to a sola-regulating transformer 408 whereit is transformed to 120 V power, as illustrated at 409. This filtered,120 V power is used to provide electrical energy to all components ofapparatus 10 other than pumps 195, 244. If electrical energy isinterrupted, three 12 V batteries 410 connected in series are providedas an uninterruptable power supply through triple power supply 412.

Remote control unit 20 has monitor screens 26, 29 and keyboards 24, 27for weighing and metering functions. Remote control unit 20 iselectrically connected through line 422 with a weigh microcomputer 424(RCA 1800 Micro System Z80 Microprocessor) having a 120 V opticallyisolated input/output relay board 426. Remote control unit 20 is alsoconnected through line 428 with machine sequencing microcomputer 430(RCA 1800 Micro System Z80 Microprocessor) having an optically isolateinput/output relay board 432 (Opto PB 24Q). Computer interface 434provides a data bus between weigh microcomputer 24 and machinesequencing computer 430.

Machine sequencing computer 430 and weigh computer 434 are supplied with5 V power from triple power supply 412 through line 411. Both I/0 boards426, 432 are supplied with 120 V power through line 436 at 438.

Weigh computer 424 contains an eight slot card cage with three 662 RAMmemory cards that contain the programs for operation of the weighingfunctions and monitoring of microingredient additive inventory. Weighcomputer 424 also contains a service box 641 card to connect the servicebox to the computer, a printer 641 output card, a 600 system operatingprogram card, and a 6264 memory card.

The machine computer 430 has a six slot card cage, including two 662 RAMmemory cards, as well as a 659, 650, 641 and 600 CPU card. Whenapparatus 10 is functioning in the metering mode, it uses only machinecomputer 430. A complete set of ration data is stored on the machinecomputer's ROM memory separate from the ration data stored on the RAMmemory cards of weigh computer 424.

I/0 board 426 is connected through line 448 with a speed control 444 forcontrolling the speed of dispensing means 80 in the weigh mode during aweigh cycle. For additives dispensed in weigh mode, speed control 444determines whether screw 90 rotates at a fast speed during the initialweighing period of a given concentrate, or at a slow speed during theterminal phase of weighing as the weight of the concentrate approachesits predetermined amount. Since it is necessary to sense the weight ofeach concentrate that has been dispensed before the speed of dispensingmeans 80 can be reduced and then stopped, load cells 264 areelectronically connected through scale head 418 to the weighmicrocomputer 424. Weight determinations of the weighing means cantherefore be sensed and sent to speed control 444. For additivesdispensed by volume during a weigh cycle, speed control 444 determinesthat screw 90 rotates at the preset third speed during the predeterminedtime of volumetric dispensing controlled by micro computer 430.

I/0 board 432 is connected through line 446 with speed control 444 forcontrolling the speed of dispensing means 80. Speed control 444determines that screw 90 rotates at the preset metering speed on thethird speed of speed control 444 for a predetermined amount of time ofvolumetric dispensing controlled by microcomputer 430.

Input/output board 432 is connected through line 440 with ingredientlevel controls 442 in each of bins 68-74 and containers 76, 78. Theselevel controls are conventional switches located within the bins andcontainers for sensing when the level of additive concentrate in eachbin has reached a predetermined low level. When the low level ofadditive concentrate is sensed by low level control 42, a signal is sentto the operator indicating that more concentrate should be added.

I/0 board 432 of machine sequencing microcomputer 430 is connectedthrough line 450 and relay 452 with hopper rotation motor 138 thatinverts hopper means 122. Line 456 connects I/0 board 432 through relay458 with vibrator 141 on hopper means 122. A switch 462 is also providedon hopper means 122 for sensing whether the hopper is in an upright orinverted position, switch 462 being connected to I/0 board 432 throughline 464. Finally, hopper means 122 is provided with hopper air flushsolenoid valve 466 in header 150 for controlling the introduction of airflush into compartments 113-116 of the hopper after it reaches itsinverted position. Solenoid valve 466 is connected to I/0 board 432through line 468.

Mixer motors 188 on mixing vessel 170 are connected through relay 470and line 472 with I/0 board 432. Level control 192 of the mixing vesselis connected with I/0 board 432 through line 474. Solenoid valve 212 inflush line 202 is connected to I/0 board 432 through line 476, andsolenoid 206 in fill line 204 is connected to I/0 board 432 through line478. Booster pump 195 for pumping water into vessel 170 is connectedthrough relay 406 and line 480 with I/0 board 432, while pump 244 forwithdrawing slurry and flush water from vessel 170 is connected throughrelay 407 and line 482 with I/0 board 432. Low water control 484 for thewater supply is connected through line 485 with the I/0 board. Motionand panel control sensors 486, which detect any oscillatory movements ofhopper means 122 and determine if any of the panels 12 have been removedfrom apparatus 10, are interconnected with I/0 board 432 through line490.

Metering Mode Program

As earlier described in connection with FIG. 12, in the event of scalefailure at step 317, apparatus 10 switches to a meter mode at 318 andthe weigh switch is turned off at 319. The off position of the weighswitch at 319 is sensed as the meter switch being on at step 500 in FIG.15. The numeral 1 is entered at keyboard 24 at step 502 to beginbatching in the metering mode, and a ration code name is entered at 504.The metering mode program of FIG. 15 searches at 506 for a rationcorresponding to the code entered at 504. If the corresponding ration isnot found at 506, the program returns at 508 to step 504 so that anotherration name can be entered.

Once the entered code has been matched with a ration at 506, the programprompts for entry of information concerning batch size, which is enteredat 509. The program next prompts for entry of information concerning thenumber of batches to be processed, which is entered at 510. The machineis then ready to batch at 512 by volumetric metering instead of byweighing.

The program waits at step 514 for a start signal 516, which is suppliedby a start switch 299 on control panel 28. It is then determined at 518if boost pump 193 is on, and if it is not, an alarm is given at 520 toindicate that the pump is off. Boost pump 193 fills mixing vessel 170during a predetermined amount of time at step 522. If the water level inmixing vessel 170, as detected by water level sensor 192, does not reacha predetermined level within a set period of time, an alarm sounds at524 to indicate a filling error.

Once level sensor 192 determines that the water level in mixing vessel170 has reached a predetermined level, mixing motors 188 are activatedat 526 to rotate mixing blades 182 at a slow speed. An alarm sounds atstep 528 if the mixers are not on. While mixer blades 182 induce aturbulent flow of water in mixing vessel 170, motor 102 for screw 90below bin 68 is activated at 530. The metering speed of motor 102 is athird speed, intermediate the fast and slow speeds used in dispensingadditive concentrates by weight. Screw 90 turns for a predeterminedperiod of time sufficient to dispense a required volume of additiveconcentrate. The screw of each dispensing means 80 below the binscontaining desired additive concentrates turn simultaneously. Dispensingmeans 120 for liquid additive concentrates in containers 76, 78 alsooperate simultaneously with dispensing means 80 to volumetricallydeliver predetermined amounts of liquid concentrate to compartments 117,118.

When metering is complete at 532, a signal is sent to motor 138 at step534 to invert hopper means 122 and dump its contents into the flowingwater of vessel 170. A switch determines at 536 whether the hopper isinverted, and if it is not, an alarm is given at 538 to indicate a dumpfailure. Hopper vibrators are then actuated at 540 while hopper means122 is inverted to remove, by vibration, additive concentrate particlesthat remain stuck to the walls or bottom of containers 113-116. The airflush (FIG. 11) is actuated at 542, and the program sends a signal at544 to send the hopper to its home, upright position by actuating motor138 to continue rotation of shaft 136. If hopper means 122 does notreach its home, upright position within a predetermined period of timeset by 546, an alarm sounds at 548 to indicate that a malfunction hasoccurred and the hopper is still inverted.

When hopper means 122 leaves its inverted position, mixing motors 188are switched to their second, higher speed at 548. High speed mixingcontinues for a predetermined amount of time and then returns to lowspeed at step 550 until a discharge signal 554 is received at 552 from adischarge switch 383 on panel 28 to turn on discharge pump 244. It isdetermined at 556 whether discharge pump 244 is on, and if it is not, analarm is given at 558 to indicate a pump malfunction.

A predetermined, mix delay time period is initiated at 558 during whichperiod motors 188 continue to move mixing blades 182 at low speed. Ifthe bottom of level probe 192 is not cleared at 560 within thepredetermined period of time set in step 558, an alarm is given at 562to indicate pumping problems. Once probe 192 has been cleared, apredetermined flush cycle time is initiated at 564, and boost pump 193is actuated at 566 to move water through flush line 214 while solenoid212 is open and solenoid 206 is closed. Boost pump 193 continuesintroducing water through line 214 and into flush ring 226, bladecleaning nozzles 224, and port 177 until a flush period has expired at568 and pump 193 is turned off at 570. Discharge pump 244 continuesoperating for a period of time set by 572 until all of the flush waterresidue has been removed through drain 178 and sent to receiving station248. Discharge pump 244 is then turned off at 574 when the delay periodset at step 572 expires.

The metering mode program then determines whether another batch isneeded at 576, the need for another batch having been determined by thenumber of batches entered at 310. If another batch is not needed, theprogram returns to step 502 which prompts the operator to enter the codefor another batch. If, on the other hand, another batch is required at576, the program checks at 578 to determine if the meter switch is stillon. If the metering switch is on (and conversely the weigh switch isoff), the program returns to step 512 where it repeats steps 512-576. Ifit is determined at 578 that the meter switch is off, apparatus 10 isturned off at 580 and an alarm is given at 582 indicating a mode change.

FIG. 16 Embodiment

FIG. 16 shows a second embodiment of apparatus 10 in which hopper means122 has been eliminated. In this embodiment, the weight of eachmicroingredient concentrate dispensed is determined on a "loss ofweight" basis. Each of dry concentrate bins 600, 602, 604, 606 isprovided with a load cell 608 for determining the weight of eachcontainer. The program in this embodiment activates a dispensing means610 (similar to dispensing means 80 in apparatus 10) to selectivelysequentially or simultaneously deliver dry microingredients separatelyfrom bins 600-606 into mixing vessel 612 having mixers 614, 616. Tank612 is filled and flushed through water supply line 618 and emptiedthrough discharge line 620 after concentrates have been mixed with waterin mixing vessel 612.

Liquid microingredient concentrates may also be dispensed on a "loss ofweight" basis by mounting containers of liquid microingredient on loadcells.

The control means for the FIG. 16 embodiment includes a means forcontrolling the dispensing rate of each dispensing means 610 in responseto loss of weight sensings of load cell 608 for each bin 600-606. Such acontrol means is similar to speed control 444 for dispensing means 80 inFIG. 14.

In a variation of the embodiment of FIG. 16, the control means includesa means for operating dispensing means 510 for several cycles in thevolumetric metering mode wherein additives are dispensed using a weightper unit time formula instead of load cell 608. The actual weight ofeach additive concentrate dispensed will be determined by the loss ofweight measured by each load cell 608. The actual weight of concentratelost will be compared by the computer to the theoretical amountdispensed. The discrepancy between the actual and theoretical amountswill then be corrected by adjusting the formula to dispense moreaccurately the desired amount of additive concentrate. Since theremaining concentrate in each bin has substantially the same density asthat already dispensed, the remaining additive can be dispensedaccurately by volume.

Correction of the weight per unit time formula used for volumetricdispensing in the metering mode can be used in connection with anyembodiment employing a weighing means. For example, volumetric meteringinto hopper means 122 of FIG. 2 can be adjusted by comparing actualweights of additive concentrate dispensed into compartments 113-116 withthe desired amounts determined on a weight per unit time formula. Thecomputer can then correct the formula to account for the density andother properties of the particular batch of additive concentrate beingdispensed.

Alternatively, dispensing means 80 can be operated in a weigh mode fromthe beginning through a major portion of a dispensing cycle for aparticular additive concentrate. The load cell 264 monitors the weightof concentrate dispensed at a given speed of screw 90. This informationis used by the control means to prepare a weight per unit time formulafor volumetric dispensing of the particular additive being dispensed.The dispensing means 80 is then operated in a volumetric metering modeindependently of the weighing means for the final portion of thedispensing cycle.

FIG. 17 Embodiment

Yet another embodiment of the invention is shown in FIG. 17 which takesadvantage of the fact that the density of liquid microingredientconcentrates does not vary as greatly as solid microingredients. Forthis reason, it is possible to accurately meter liquid microingredientsby volume while measuring the solid microingredients by weight. In theembodiment of FIG. 17, four dry microingredient containing supply means701, 702, 704, 708 are shown to each be connected to a dispensing means710 similar to the dispensing means 80 of apparatus 10. Each ofdispensing means 710 conveys dry additive concentrate to a hopper means712 similar to hopper means 122 in FIG. 5, the hopper means 712 beingsuspended from a pair of weigh cells. Each additive concentrate isdispensed sequentially into hopper means 712 from containers 701, 702,704, 708 using dispensing means 710 until a predetermined weight of eachconcentrate has been sensed by a load cell from which hopper means 712is suspended. Hopper means 712 is then inverted to separately andsimultaneously empty the dry microingredient contents of hopper means712 into flowing water in mixing vessel 714 which is being agitated bymixers 716, 718.

In the FIG. 17 embodiment, liquid microingredients are separately storedin containers 720, 722 which are provided with tubes 724 that empty intovessel 714. Rotary or piston pumps 728 are interposed in each tube 724to pump microingredients from containers 720, 722 directly into mixingvessel 714, thereby bypassing entirely hopper means 712.

The control means for the FIG. 17 embodiment may, in some embodiments,include means for selectively operating some dispensing meanssimultaneously and others sequentially. Pumps 728 for the liquidadditive concentrates in containers 720, 722 may, for example, beoperated simultaneously with each other and with dispensing means 710.Dispensing means 710 for dry additives should, however, be operatedsequentially in this embodiment since the overall weight of hopper means712 is sensed by the load cells from which the hopper is suspended. Ifthe dry additives were dispensed simultaneously into hopper means 712,it would not be possible to weigh accurately the amount of each additivedispensed. It is through cumulative weight determinations ofsequentially dispensed additives that accurate weight determinations aremade in the compartmented hopper. A first additive concentrate isdelivered into a compartment of the hopper until its load cells registera first predetermined weight, and delivery of the first additiveconcentrate is stopped. Delivery of a second additive concentrate isthen started and continued until the load cells register a secondpredetermined weight, and so on until predetermined weights of allselected additives have been delivered into the hopper.

In yet other embodiments which are not shown in the drawings, thecontrol means is programmed to operate the dispensing means in aninterrupted, on-off-on-off sequence to dispense selectedmicroingredients into a weighing means such as hopper 122. Weightdeterminations sensed by load cells 264 would only be accepted when thedispensing means is switched off during the interrupted sequence. Inthis manner, weighing inaccuracies caused by movement of the dispensingmeans or settling of additives would not affect weight determinations.

In another disclosed embodiment, the isolating means includesprogramming the control means to prevent operation of any other movingcomponents of apparatus 10 while weight determinations are being made bythe weighing means. The operation of dispensing means 80 and mixerblades 182 would, for example, be prevented by the control means whileweight determinations were being made by load cell 264.

FIG. 18 Embodiment

FIG. 18 shows an apparatus indicated generally at 800 in accordance withthe invention and somewhat similar to the embodiment of FIGS. 1-15 buthaving two separate weigh hoppers 802, 803 for weighing the multipleadditive concentrates dispensed from additive concentrate storage means805, 806 by dispenser means 808. The weigh means of the apparatus 800includes separate weigh means for each weigh hopper 802, 803, therebygiving the apparatus the capability of weighing multiple additivessimultaneously in different weigh hoppers. This capability gives theapparatus 800 an advantage over the apparatus of FIG. 1 in being able todispense, weigh and discharge all of the multiple microingredients of agiven formulation into the mixing vessel 810 and thereby complete thebatching of a formulation, more quickly than the apparatus of FIG. 1.

The apparatus 800 also includes a support frame means 812 which mayinclude either separate support and weigh frames as in the apparatus ofFIG. 1 or a common support frame for all of the major mechanicalcomponents of the apparatus as depicted schematically in FIG. 18.Support frame 812 rigidly supports the multiple microingredientconcentrate storage containers 805, 806 and their associated dispensersor metering devices 808, 809. The support frame means 812 also rigidlysupports the mixing vessel 810 which is shown as a mixing vessel commonto both weigh hopper 802 and weigh hopper 803.

Other major components of the system of FIG. 18 include control andother components which would normally be mounted apart from supportframe means 812, including a pair of scale heads 814, 815, one for eachweigh hopper, a weigh computer or central processing unit 817 with itsassociated input/output board 818, and a remote control unit or terminal820 for controlling the operation of the computer 817. A separatemachine computer or central processing unit 822 has an associatedinput/out board 823. An interface 824 enables communication between themachine computer 822 and the weigh computer 817. Scale heads 814, 815transmit weight determination data through line 826 to the input/outputboard of the weigh computer 817. There is also a printer 828 connectedto the input/output board of weigh computer 817 through line 830 forprinting desired output data from the weigh computer 817.

In the apparatus 800 there are four microingredient additive concentratestorage containers 805 associated with weigh hopper 802 and another foursuch storage containers 806 associated with the other weigh hopper 803,thereby giving each weigh hopper the capability of weighing anddischarging four different additives into the mixing vessel 810. Thedispensers 808 associated with the different additive storage containers805 are capable of operating independently of one another upon anappropriate command signal from a weigh computer 817 transmitted fromthe input/output board 818 through line 832. Similarly, each of thedispensers 809 for the four other storage containers 806 are capable ofoperating independently of one another to dispense additives into theweigh hopper 803 upon a suitable command signal from weigh hopper 817transmitted from input/output board 818 through line 834.

Weigh hopper 802 is mounted at its opposite ends on a pair of load cells836, 837 connected by suspension members 838, 839 and a pair ofresilient isolator members 840, 841 to support frame 812.

Weigh hopper 803 is mounted in a similar manner by load cells 842, 843to support frame 812. Thus, each weigh hopper is independently mountedby separate weigh means to the frame 812 for independent weighing ofingredients. The two load cells 836, 837 for weigh hopper 802 areoperatively connected by a line 845 to scale head 815. Weigh hopper 803is separately connected by a line 846 to a separate scale head 814. Bothof the scale heads in turn are connected to the input/output board 818of weigh computer 817 through line 826. Thus each weigh hopper and itscontents can be weighed separately and its contents cumulatively throughits associated scale head simultaneously with the other weigh hopper.That is, both weigh hoppers can carry out their weighing functions atthe same time and independently of one another.

Each weigh hopper 802, 803 is preferably similar in construction to theweigh hopper disclosed in FIGS. 2, 3, 5, 6 and 7. That is, each weighhopper is mounted in a manner shown in such prior figures for rotationfrom its normal additive receiving upright position to an inverteddischarge position by discharge means including an electric motor 848 inthe case of weigh hopper 802 and electric motor 849 in the case of weighhopper 803. Each is connected independently to the input/output board823 of the machine computer 822 through suitable electrical conductors850 and 851, respectively.

Each weigh hopper, 802, 803 also is provided with a motion sensor 853,854, respectively, connected to the input output board 818 of weighcomputer 817 through line 856 for detecting any motion in either weighhopper during the weighing process. The software for the weigh computer817 prevents a final weight determination from being made for a givenweigh hopper whenever the motion sensor for that hopper senses motionthat might give a false or highly inaccurate reading.

The support frame means 812 for the weighing and delivery components ofthe apparatus is preferably enclosed by housing panels (not shown) in amanner similar to that shown in FIG. 1 to shield and isolate theweighing components of the apparatus from external ambient forces thatcould cause undesirable motion and thus inaccurate weight readings. Suchforces typically might include the effects of wind or jarring of thecomponents by direct contact of personnel. The support frame means 812is provided with a sensor 858 which is also connected by line 856 to theinput/output board of weigh computer 817. Sensor 858 is operable toprevent a weight determination from being made whenever a panel isremoved from the support frame 812. Thus the motion sensors 853, 854 forthe weigh hoppers and the panel sensor 858 for support frame 812 provideadditional means for isolating the weighing components of the apparatusfrom influences that could affect weight determinations and theaccuracies of such determinations.

A further means of enhancing the accuracy of the weight determinationsof the apparatus disclosed in FIG. 18 is the mounting of the dischargemotors 848 and 849 in conjunction with their respective weigh hoppers802, 803 so that such motors become part of the tare weight of thehoppers in making additive weight determinations. Because verylightweight, flexible electrical conductors can connect such electricmotors to the operable control components of the apparatus, suchconductors will have no appreciable effect on the weight determinationsof the weigh means. This should be contrasted with the hydraulicallyactuated discharge means in conjunction with the weigh hoppers of priorapparatus. With a prior hydraulically actuated discharge means,relatively stiff hydraulic conduit must connect the hydraulic motorassociated with the hopper to the source of hydraulic fluid remote fromthe hopper. Typically such hydraulic conduit affects weightdeterminations of the hopper in such instances because it inherentlyprovides some structural support for the hopper, thereby influencingload cell weight sensings as ingredients are added to the hopper becausethe conduit is partially supporting some of the load of the addedweight.

The apparatus in FIG. 18 also includes positive mixing means within themixing vessel 810 in the form of a pair of mixing blades 860, 861, eachdriven by an electric motor 862, 863. The mixer motors are connected byelectrical conductor means 864 to the input/output board 823 of themachine computer 822. A slurry discharge line 866 leads from a bottomopening of mixing vessel 810 to the input side of a discharge pump 868.The discharge line continues at 870 from the discharge side of dischargepump 868 to a conventional feed mixer such as typically thetruck-mounted feed mixer 872. A booster pump 874 pumps a liquid carriersuch as water from a source (not shown) through a fill line 876 into themixing vessel. A solenoid operated valve 878 in fill line 876 controlsthe admission of the water carrier into the mixing vessel and isoperated by the machine computer 822 through a suitable conductor 878connected to the input/output board 823 of such computer.

A flush line 880 branches from fill line 876 downstream of booster pump874 and upstream of fill valve 874. Another solenoid actuated valve 882in the flush line connected to the input/output board 823 of machinecomputer 822 through conductor 884, controls the admission of flushfluid into the mixing vessel.

The hardware components of the control system including the weighcomputer 817, machine computer 823 and their associated input/outputboards, the printer 828, and the remote control unit 820, may be similarto those same units described with respect to the embodiment of FIG. 1.Similarly, the software controlling the operation of such computers canbe varied to vary the operating sequence of the machine of FIG. 18.

A typical operating sequence of the machine of the apparatus of FIG. 18is as follows:

A driver drives a feedtruck into a feed-receiving station in a cattlefeedlot. The driver departs his vehicle, approaches the remote controlunit 820 and selects the formulation of feed additive concentrates to bebatched and delivered into his truck, depending on the specific lot ofanimals to be fed within the feedlot. The formulation is selectedtypically by the operator depressing a key corresponding to theformulation selected on the computer terminal of the remote controlunit.

Assuming that predetermined weights of two additives A1, A2 in storagecontainers 805 and two additives A5, A6 from storage containers 806 areto be included in the formulation, the dispenser 808 for container A1begins to dispense the additive A1 into weigh hopper 802. At the sametime, the dispenser 809 for container A5 begins to dispense additive A5into weigh hopper 803. The dispensing of additive A1 into weigh hopper802 continues until a predetermined weight of such additive has beenadded to such hopper as determined by the load cells 836, 837 and theassociated scale head 815, at which point the weigh computer 817 stopsthe dispensing of additive Al from its storage container by stopping itsassociated dispensing means 808. At the same time, a weightdetermination of the additive A5 added to weigh hopper 803 is determinedin the same manner, but independently of the weight determinationoccurring in hopper 802.

When the predetermined weight of additive A1 has been added to weighhopper 802, depending on programming, two alternative functions canoccur. Either the weigh hopper 802 can be inverted by motor 848 todischarge the additive Al into the mixing vessel 810 and then returnedto its upright position to receive the next additive A2, or the weighhopper can remain in its upright position while the dispenser 808 foradditive A2 operates to add, cumulatively, the predetermined weight ofadditive A2 to weigh hopper 802. If the latter sequence is used, weighhopper 802 is inverted by its discharge motor 848 to discharge thepredetermined weights of additive Al and additive A2 together into themixing vessel 810. The same options are available with respect to theaddition of additives A5 and A6 to weigh hopper 803 and the discharge ofthe contents of the weigh hopper 803 into the mixing vessel 810. It isimportant to note that both weigh hoppers 802 and 803 can operateentirely independently to weigh and discharge their preselectedadditives into the mixing vessel 810, although the machine and weighcomputers could also be programmed to cause both weigh hoppers 802, 803to wait until all of the selected additives have been added and weighedwithin each weigh hopper and then both weigh hoppers invertedsimultaneously by their respective motors to discharge all of theweighed additives at once into the mixing vessel. That is, each additivecan be added, weighed and discharged either separately or cumulativelywith other additives, depending on the programming selected for thecontrol system.

Regardless of which of the above described dispensing, weighing anddischarge options are selected, preferably booster pump 874 pumps thecarrier water through open valve 874 and fill line 876 to fill themixing vessel 810 to a predetermined level before any additive isdischarged into the mixing vessel. This will prevent different andpossibly incompatible additives from intermixing in concentrated formand also prevent additives from sticking to the inside walls of thevessel, making it difficult to remove such additives even after carrierwater or flush water is added to the vessel.

Also preferably before the discharge of any additives into the mixingvessel in making up a batch, mixing blades 860, 861 rotate to create aturbulent flow within the mixing vessel so that additives entering theliquid carrier are quickly intermixed with and dispersed throughout thecarrier, thereby diluting the concentrates.

When the predetermined weights of the selected additives A1, A2, A5 andA6 all have been weighed in their respective weigh hoppers 802, 803 anddischarged into the water carrier within mixing vessel 810, mixingblades 860, 861 continue to rotate for a time to ensure a uniformdispersal of all additives throughout the carrier liquid slurry thusformed. Of course at this time, booster pump 874 shuts off and fill linevalve 874 closes, as does flush line valve 882.

When mixing is complete within mixing vessel 810, discharge pump P2operates to pump the slurry formulation from the mixing vessel throughdischarge line 866 and to the waiting feed mixer truck 872 throughdischarge line 870. When the level of slurry within the mixing vesseldrops below a predetermined level as determined by level sensors (notshown) within the vessel, booster pump 874 restarts and flush line valve882 opens to pump flush water into the mixing vessel through its top andalong its side walls to flush all slurry residue from the vessel.Flushing continues as the discharge of slurry proceeds through thedischarge lines 866, 870. Discharge pump 868 continues to operate duringthe complete flush period, pumping the flush liquid with the slurry intothe feed mixer truck 872. After a predetermined length of timesufficient to enable the complete flushing of the mixing vessel anddischarge lines, and the pumping of all slurry into the feed mixer 872,booster pump 874 stops and flush valve 882 closes. Pump 868 continues tooperate until all of the slurry and most of the flush liquid is pumpedinto the feed mixer 872. Thereafter the truck operator returns to histruck and drives away as the mixing of the feed and slurry continues.Typically, the driver drives to the feed bunks of selected pens or lotsof animals and delivers the additive-bearing feed into the bunksimmediately upon departure from the additive receiving station.Thereafter, typically, another feed mixer truck arrives at the additivereceiving station represented by the position of truck 872 and thatoperator goes through the same procedure as just described, selectingthe same or a different formulation depending on the requirements of theanimals within the lot or pens that are to be fed with the feed rationfrom such truck.

During the additive formulating process as just described, the systemwill not allow a weight determination of a given additive to be made solong as a panel is removed from the support frame 812 as detected bysensor 858. Nor will a weight determination be made if either one of themotion sensors 853, 854 associated with each weigh hopper detectsmovement of a weigh hopper that could affect the weight determination tobe made in such weigh hopper.

Typically, scale heads 814, 815 receive weight sensings from theirrespective load cells 6 to 8 times per second. The scale heads thenaverage such readings for that given unit of time and send the averagereading via line 826 to the input/output board 818 of the weigh computer817. Computer 817 then records the averaged weight per unit of time asthe weight upon which the computer acts to control the operation of theadditive dispensing means and discharge means. Because of the largenumber of readings being averaged before the average is transmitted tothe weigh computer, any single erroneous reading transmitted to a scalehead by the load cells will have an insignificant effect on the accuracyof the averaged reading transmitted from the scale head to the weighcomputer for processing. This slow updating of the weigh computer (aboutonce per second or less) with an average of a large number of weightsensings received by the scale head is further insurance againstinaccurate weight readings and enhances the accuracy of the entiresystem. If the computer updating were faster (such as twice per secondor more), an erroneous reading would have a greater effect on theaccuracy of weights recorded and processed by the computer.

FIG. 19 Embodiment

FIG. 19 is a flowchart of a computer program applicable to the computersof FIG. 14 and representing a modification of the program of FIG. 15 foroperating the apparatus of, for example, FIG. 16 on a weight-compensatedmetering basis.

The flowchart of FIG. 19 incorporates steps 500-530 of the FIG. 15program in box 900 and also the completion-of-metering step 532 of thesame program. When all microingredients have been metered into themixing vessel 612, the program continues to sequence through steps549-582 of the metering program of FIG. 15, skipping steps 534-548because the apparatus of FIG. 16, unlike the apparatus of FIGS. 14 and18, does not use a weigh hopper.

As the program continues to sequence through mixing and discharge steps549-582 as indicated at box 902 in FIG. 19, the program also, at leastafter so many metering cycles, or if desired after every metering cycle,reads the weight of each microingredient storage container 600, 602,604, 606 as indicated at 904. Thereafter, as indicated at box 906, theprogram commands the computer to calculate the actual loss of weight ofthe ingredient storage containers to determine the actual weight of eachmicroingredient metered, by subtracting the weight of each storagecontainer sensed after metering at 904 from the initial weight of eachstorage container prior to such metering steps.

The program also commands the computer to calculate the theoreticalweight loss of each storage container, which is also the theoreticalweight of each ingredient used, by multiplying the metering rate of eachmetering device 610 in, for example, grams per minute, by the length oftime each metering device 610 has operated, as indicated at box 908. Theprogram then commands the computer to compare the actual weight ofingredient used as calculated at 906 with the theoretical or targetweight of ingredient used as calculated at 908, as indicated at box 910.From this comparison the program commands the computer to adjust eitherthe time that each metering device 610 operates, or the rate of speed atwhich each such device operates, or both, during a metering cycle sothat the actual weight of ingredient used as determined by weighingequals the desired or theoretical weight of ingredient used asdetermined by metering. This adjustment command occurs at box 912 in thecomputer program. When the metering speed or time adjustment is made,the program returns to the start of the metering cycle as indicated atbox 900.

The program also includes a fill mode or routine which is used whenevera microingredient storage bin 600, 602, 604, 606 is refilled. In suchmode, the program commands a reading of the initial weight of thestorage container being refilled at box 914. The additionalmicroingredient is then added to the storage container as indicated inbox 916. The program then commands a reading of the filled weight of thestorage container at box 918 and enters such weight in computer memory.At this point the fill subroutine has been completed and the apparatusis conditioned to start another metering cycle.

The foregoing described program operates the apparatus of FIG. 16primarily as a metering apparatus. However, the metering devices 610 areadjusted after completion of a predetermined number of metering cyclesbased on actual loss-of-weight determinations of each storage bin asregistered by the weighing means 608 for each storage container. Thusthe apparatus of FIG. 16 when operated in accordance with the program ofFIG. 19 is actually a hybrid weigh-metering system in which the meteringcomponents are periodically readjusted so that the theoretical or targetweights of ingredients metered will closely approximate the actualweights of ingredients dispensed.

The described weight-compensated metering system can also be used in acontinuous mill application in contrast to the batch mill applicationdescribed with respect to FIG. 16. In a continuous mill system, themetering devices meter the additive concentrates continuously atpredetermined rates from their storage bins into a liquid carrier, whichin turn flows into a feed ration at a predetermined rate. In such asystem, weight losses of the storage bins can be determined periodicallyand then used to calculate the necessary adjustments of metering ratesof the metering devices to bring the actual weights of additivesdispensed per unit of time by metering into line with the theoreticalweights desired. This can be done without interruption of metering,simply by adjusting the speed controls of the metering devices.

Having illustrated and described the principles of the invention inseveral preferred embodiments, it should be apparent to those skilled inthe art that the invention can be modified in arrangement and detailwithout departing from such principles. I claim all modifications comingwithin the spirit and scope of the following claims.

I claim:
 1. A method of dispensing and delivering microingredient feedadditives into a livestock feed ration shortly before delivering thefeed ration to the livestock for consumption, comprising thesteps:storing separately multiple said additives in concentrate form;dispensing predetermined weights of selected said additive concentratesinto a liquid carrier; intermixing the additive concentrates in theliquid carrier to dilute, disperse, and suspend them and form a liquidcarrier-additive slurry; directing the slurry to a receiving stationwhile maintaining the suspension and dispersion of the additives untildelivered into a feed ration; and determining the predetermined weightsof the selected additives by weighing each additive before it enters thecarrier, sensing any motion in the apparatus used to weigh eachadditive; stopping the weighing of any additive when motion is sensedthat would adversely affect the at least a final weight determination ofan additive and resuming the weighing only after the adverse motion hassubsided.
 2. A method of dispensing and delivering microingredient feedadditives into a livestock feed ration shortly before delivering thefeed ration to the livestock for consumption, comprising thesteps:storing separately multiple said additives in concentrate form;dispensing predetermined amounts of selected said additive concentratesinto a liquid carrier; intermixing the additive concentrates in theliquid carrier to dilute, disperse, and suspend them and form a liquidcarrier-additive slurry; directing the slurry to a receiving stationwhile maintaining the suspension and dispersion of the additives untildelivered into a feed ration; determining the predetermined amounts ofthe selected additives by weight; detecting a malfunction in apparatusused to weigh the additives; and determining the predetermined amountsof the selected additives on a volumetric basis if a malfunction of theweighing apparatus is detected.
 3. A method of dispensing and deliveringmicroingredient feed additives into a livestock feed ration shortlybefore delivering the feed ration to the livestock for consumption,comprising the steps:storing separately multiple said additives inconcentrate form, including some said additives in solid particulateconcentrate form and at least one of said multiple additives in liquidconcentrate form; dispensing predetermined amounts of selected saidsolid particulate concentrates by weight into a liquid carrier;dispensing predetermined amounts of selected said liquid additiveconcentrates into a liquid carrier by volume; intermixing the additiveconcentrates in the liquid carrier, including both the solid particulateadditive concentrates and the liquid additive concentrates, to dilute,disperse, and suspend them and form a liquid carrier-additive slurry;directing the slurry to a receiving station while maintaining thesuspension and dispersion of the additives until delivered into a feedration.